Published online by Cambridge University Press: 01 January 2024
Oscillating-heating X-ray diffraction was used to determine d-spacings and intensity changes of the (001) diffraction maximum for various combinations of 3 clays, 6 cations and 7 polyalcohols from 20°C to 1000°C under non-equilibrium conditions.
The temperature of collapse of the one layer complex was measured. Analysis of variance of this parameter for a model containing 3 clays, 6 cations and 7 polyalcohols showed that there is a significant difference among cations and polyalcohols but not among clays.
Additional work on one clay, 6 cations and 18 polyalcohols shows that ΔT—the difference in temperature between the collapse of the clay-organic complex and the boiling point of the polyalcohol—is proportional to the length of the carbon chain ; ΔT is also a function of the number and position of the OH groups.
The mean temperatures of final collapse for all polyalcohols are related to the valence of the interlayer cations and inversely related to their ionic radii.
There are two groups of d-spacings for the one-layer complexes. Complexes with polyalcohols having OH groups at the ends of the chain have mean d-spacings between 13.6–13.7 Å, while complexes with polyalcohols with interior OH groups have mean d-spacings of 13.9–14.0 Å.
Published by permission of the Pure Oil Company.